Application of a New Nonlinear Programming Code with Decomposition to the Regional Wastewater-Collection and Treatment-Location Problem

1976 ◽  
Vol 8 (5) ◽  
pp. 563-571
Author(s):  
L R Padgett ◽  
A H Montgomery ◽  
L Romino
Keyword(s):  
Nonlinear Programming ◽  
Economies Of Scale ◽  
Location Problem ◽  
Sewage Treatment ◽  
Optimal Solution ◽  
Cost Savings ◽  
Regional Model ◽  
Programming Algorithm ◽  
Trade Offs ◽  
The Cost

A new, highly reliable nonlinear programming algorithm is coupled with decomposition to find the optimal solution to a regional sewage-treatment system for an area in Monongalia County surrounding Morgantown, West Virginia. A regional model with trade-offs between the cost of transporting wastewater to centrally located plants for treatment and the economies of scale accruing to large centralized treatment plants is developed. Possible cost savings of an optimal system are demonstrated.

Student Laptop Ownership Requirement and Centralization of Information Technology Services at a Large Public University

2011 ◽  
pp. 201-212 ◽  
Author(s):  
Gregory B. Newby
Keyword(s):  
Information Technology ◽  
Economies Of Scale ◽  
Cost Savings ◽  
Leading Edge ◽  
Chief Information Officer ◽  
Public University ◽  
General Purpose ◽  
Information Technology Services ◽  
Technology Services ◽  
The Cost

A large, highly ranked public university implemented a requirement for all incoming undergraduates to own a laptop computer starting in fall, 2000. To control increased expenditures for information technology, this requirement has shifted some of the cost of technology to students by decreasing the need for centralized general-purpose computing laboratories. At the same time, a shift towards centralized academic computing support occurred. This shift was away from information technology resources, services and support based in individual departments. This shift, engineered by the newly formed office of the Chief Information Officer (CIO), was envisioned to generate cost savings through economies of scale. The educational impact of the laptop requirement is starting to be felt, but adoption is not widespread in daily classroom use. Envisioned cost savings have not yet become apparent. However, laptop ownership has enabled some new classroom activities and helped to reinforce the leading-edge image of the university.

Student Laptop Ownership Requirement and Centralization of Information Technology Services at a Large Public University

2006 ◽  
pp. 163-175
Author(s):  
Gregory B. Newby
Keyword(s):  
Information Technology ◽  
Economies Of Scale ◽  
Cost Savings ◽  
Leading Edge ◽  
Chief Information Officer ◽  
Public University ◽  
General Purpose ◽  
Information Technology Services ◽  
Technology Services ◽  
The Cost

A large, highly ranked public university implemented a requirement for all incoming undergraduates to own a laptop computer starting in fall, 2000. To control increased expenditures for information technology, this requirement has shifted some of the cost of technology to students by decreasing the need for centralized general-purpose computing laboratories. At the same time, a shift towards centralized academic computing support occurred. This shift was away from information technology resources, services and support based in individual departments. This shift, engineered by the newly formed office of the Chief Information Officer (CIO), was envisioned to generate cost savings through economies of scale. The educational impact of the laptop requirement is starting to be felt, but adoption is not widespread in daily classroom use. Envisioned cost savings have not yet become apparent. However, laptop ownership has enabled some new classroom activities and helped to reinforce the leading-edge image of the university.

scholarly journals Greedy Algorithm for Minimizing the Cost of Routing Power on a Digital Microgrid

Energies ◽  
2019 ◽  
Vol 12 (16) ◽  
pp. 3076 ◽  
Author(s):  
Zhengqi Jiang ◽  
Vinit Sahasrabudhe ◽  
Ahmed Mohamed ◽  
Haim Grebel ◽  
Roberto Rojas-Cessa
Keyword(s):  
Optimal Solution ◽  
High Complexity ◽  
Distributed Energy ◽  
Optimal Method ◽  
Cost Rate ◽  
Trade Offs ◽  
Lower Complexity ◽  
Cost Paths ◽  
The Cost ◽  
Selection Of

In this paper, we propose the greedy smallest-cost-rate path first (GRASP) algorithm to route power from sources to loads in a digital microgrid (DMG). Routing of power from distributed energy resources (DERs) to loads of a DMG comprises matching loads to DERs and the selection of the smallest-cost-rate path from a load to its supplying DERs. In such a microgrid, one DER may supply power to one or many loads, and one or many DERs may supply the power requested by a load. Because the optimal method is NP-hard, GRASP addresses this high complexity by using heuristics to match sources and loads and to select the smallest-cost-rate paths in the DMG. We compare the cost achieved by GRASP and an optimal method based on integer linear programming on different IEEE test feeders and other test networks. The comparison shows the trade-offs between lowering complexity and achieving optimal-cost paths. The results show that the cost incurred by GRASP approaches that of the optimal solution by small margins. In the adopted networks, GRASP trades its lower complexity for up to 18% higher costs than those achieved by the optimal solution.

scholarly journals Forward Link Optimization for the Design of VHTS Satellite Networks

Electronics ◽  
2020 ◽  
Vol 9 (3) ◽  
pp. 473 ◽  
Author(s):  
Flor G. Ortiz-Gomez ◽  
Ramón Martínez ◽  
Miguel A. Salas-Natera ◽  
Andrés Cornejo ◽  
Salvador Landeros-Ayala
Keyword(s):  
Cost Model ◽  
High Capacity ◽  
Optimal Solution ◽  
Satellite Networks ◽  
Forward Link ◽  
User Terminal ◽  
Trade Offs ◽  
Service Areas ◽  
Optimum Solution ◽  
The Cost

The concept of geostationary VHTS (Very High Throughput Satellites) is based on multibeam coverage with intensive frequency and polarization reuse, in addition to the use of larger bandwidths in the feeder links, in order to provide high capacity satellite links at a reduced cost per Gbps in orbit. The dimensioning and design of satellite networks based on VHTS imposes the analysis of multiple trade-offs to achieve an optimal solution in terms of cost, capacity, and the figure of merit of the user terminal. In this paper, we propose a new method for sizing VHTS satellite networks based on an analytical expression of the forward link CINR (Carrier-to-Interference-plus-Noise Ratio) that is used to evaluate the trade-off of different combinations of system parameters. The proposed method considers both technical and commercial requirements as inputs, including the constraints to achieve the optimum solution in terms of the user G/T, the number of beams, and the system cost. The cost model includes both satellite and ground segments. Exemplary results are presented with feeder links using Q/V bands, DVB-S2X and transmission methods based on CCM and VCM (Constant and Variable Coding and Modulation, respectively) in two scenarios with different service areas.

scholarly journals Stability of Solutions for Parametric Inverse Nonlinear Cost Transportation Problem

Mathematics ◽  
2020 ◽  
Vol 8 (11) ◽  
pp. 2027
Author(s):  
Abd Allah A. Mousa ◽  
Yousria Abo-Elnaga
Keyword(s):  
Nonlinear Programming ◽  
Transportation Problem ◽  
Feasible Solution ◽  
Optimal Solution ◽  
Solution Stability ◽  
Tuning Parameters ◽  
Input Parameters ◽  
Feasible Alternative ◽  
The Stability ◽  
The Cost

This paper investigates the solution for an inverse of a parametric nonlinear transportation problem, in which, for a certain values of the parameters, the cost of the unit transportation in the basic problem are adapted as little as possible so that the specific feasible alternative become an optimal solution. In addition, a solution stability set of these parameters was investigated to keep the new optimal solution (feasible one) is unchanged. The idea of this study based on using a tuning parameters λ∈Rm in the function of the objective and input parameters υ∈Rl in the set of constraint. The inverse parametric nonlinear cost transportation problem P(λ,υ), where the tuning parameters λ∈Rm in the objective function are tuned (adapted) as less as possible so that the specific feasible solution x∘ has been became the optimal ones for a certain values of υ∈Rl, then, a solution stability set of the parameters was investigated to keep the new optimal solution x∘ unchanged. The proposed method consists of three phases. Firstly, based on the optimality conditions, the parameter λ∈Rm are tuned as less as possible so that the initial feasible solution x∘ has been became new optimal solution. Secondly, using input parameters υ∈Rl resulting problem is reformulated in parametric form P(υ). Finally, based on the stability notions, the availability domain of the input parameters was detected to keep its optimal solution unchanged. Finally, to clarify the effectiveness of the proposed algorithm not only for the inverse transportation problems but also, for the nonlinear programming problems; numerical examples treating the inverse nonlinear programming problem and the inverse transportation problem of minimizing the nonlinear cost functions are presented.

OIL AND THE ENVIRONMENT - CALIFORNIA CASE STUDY

1976 ◽  
Vol 16 (1) ◽  
pp. 137
Author(s):  
D. W. Barnett
Keyword(s):  
Energy Production ◽  
Social Cost ◽  
Shadow Price ◽  
Optimal Solution ◽  
Minimum Cost ◽  
Gulf Of Alaska ◽  
Outer Continental Shelf ◽  
Trade Offs ◽  
The Cost ◽  
Prudhoe Bay

USA environmentalists have tended to oppose all new energy developments. Their efforts may be counterproductive because opposition to, say, offshore oil directly leads to the continued use of other energy sources that may have a higher social cost. Rather than attempting to eliminate all pollution from energy production, which would be prohibitively expensive, one should minimize the social cost of energy production for the given demand.Linear programming is used to rank various oils (California State and Outer Continental Shelf (OCS), Gulf of Alaska, Prudhoe Bay, Athabasca tar sands, oil shale and certain foreign crudes) in terms of their social desirability. The objective is to minimize the cost of supplying the California market, subject to resource, sulphur and oil spill constraints.Social desirability is indicated by the inclusion of the oil in the optimal solution and the size of the associated shadow price. The larger the shadow price, the greater the benefits of increased production. The more negative, the greater the cost associated with forcing consumption of that fuel. The environmental shadow prices indicate the size of the trade-off between a particular environmental standard and minimum cost. The trade-offs can be surprisingly large. Any reasonable spill standard can be achieved by changing the development pattern. Generally, the further offshore, the smaller is the environmental degradation, but the more expensive is the oil. Foreign oils can be economically and environmentally inferior to domestic oils. Crude from the California OCS, San Joaquin Valley and Prudhoe Bay appears a valuable resource, while the Gulf of Alaska, synthetic and foreign crudes appear marginal to submarginal.The methodology could be readily adapted to the Australian scene.

scholarly journals 1209. Expanding an Economic Evaluation of the Veterans Affairs Initiative to Prevent Methicillin-Resistant Staphylococcus aureus Infections to Include Prevention of Gram-Negative Bacteria

2018 ◽  
Vol 5 (suppl_1) ◽  
pp. S366-S367
Author(s):  
Richard E Nelson ◽  
Michihiko Goto ◽  
Matthew Samore ◽  
Makoto Jones ◽  
Vanessa Stevens ◽  
...  
Keyword(s):  
Cost Effectiveness ◽  
Cost Savings ◽  
Veterans Affairs ◽  
Economic Evaluations ◽  
Published Data ◽  
Department Of Veterans Affairs ◽  
Gram Negative ◽  
Trade Offs ◽  
Life Years ◽  
The Cost

Abstract Background In October 2007, the Department of Veterans Affairs (VA) launched the National MRSA Prevention Initiative, a nationwide effort to reduce MRSA transmission through (1) universal screening, (2) contact isolation for MRSA+ patients, (3) institutional culture change that “infection prevention is everyone’s business,” (4) emphasis on hand hygiene, and (5) increased infection control resources. While the initiative focused on MRSA, recent evidence suggests that it also led to a significant decrease in hospital-onset (HO) Gram-negative rod (GNR) bacteremia. The objective of this analysis was to evaluate the cost-effectiveness and the budget impact of the initiative taking into account both MRSA and GNR infections. Methods We developed an economic model using published data on the rate of MRSA HAIs and HO-GNR bacteremia in the VA from October 2007 to September 2015, estimates of the attributable cost and mortality of these infections, and the costs associated with the intervention obtained through a microcosting approach. We explored several different assumptions for the rate of infections that would have occurred if the initiative had not been implemented. Effectiveness was measured in life-years (LYs) gained. Results We found that during fiscal years 2008–2015, the initiative resulted in an estimated 4,761–9,236 fewer MRSA HAIs and 1,447–2,159 fewer HO-GNR bacteremia. The initiative itself was estimated to cost $206 million over this 8-year period while the cost savings from prevented MRSA HAIs ranged from $75–165 million and from prevented HO-GNR bacteremia ranged from $42–62 million. The incremental cost-effectiveness of the initiative ranged from $12,146–$46,500/LY when just including MRSA HAIs and from $7,945–$24,387/LY when including HO-GNR bacteremia. The overall impact on the VA’s budget ranged from $200–$334 million. Conclusion An MRSA surveillance and prevention strategy in VA may have prevented a substantial number of MRSA and GNR infections. The savings associated with the prevented infections helped to offset some but not all of the cost of the initiative. Economic evaluations of these interventions can help decision makers understand the trade offs between increased cost and improved health that can come from such interventions. Disclosures All authors: No reported disclosures.

scholarly journals Productivity growth, economies of scale and scope in the water and sewerage industry: The Chilean case

PLoS ONE ◽  
2021 ◽  
Vol 16 (5) ◽  
pp. e0251874
Author(s):  
Maria Molinos-Senante ◽  
Alexandros Maziotis
Keyword(s):  
Productivity Growth ◽  
Technical Change ◽  
Economies Of Scale ◽  
New Technologies ◽  
Cost Savings ◽  
Policy Implications ◽  
Scale Efficiency ◽  
Water And Sewerage Industry ◽  
The Cost ◽  
Quadratic Cost Function

Evaluating the performance and analyzing the cost drivers of water utilities is of great interest for water regulators and water sector managers. This study uses a quadratic cost function to investigate the existence of economies of scale and scope in the Chilean water and sewerage industry over the period 2010–2017. We also estimate and decompose productivity growth into technical change and scale efficiency change. Technical change is further broken into pure, non-neutral and scale-augmenting technical change. The results indicate that cost savings can be achieved by increases in the scale of production and the separation of water and sewerage services. Productivity progressed favorably throughout the whole period at an annual rate of 8.4%, which was attributed to the scale effect, the adoption of new technologies and a good allocation of resources. Some policy implications are finally discussed based on our findings.

scholarly journals Forward Link Optimization for the Design of VHTS Satellite Networks

2020 ◽  
Author(s):  
Flor G. Ortiz-Gomez ◽  
Ramón Martínez ◽  
Miguel A. Salas-Natera ◽  
Andrés Cornejo ◽  
Salvador Landeros-Ayala
Keyword(s):  
Cost Model ◽  
High Capacity ◽  
Optimal Solution ◽  
Satellite Networks ◽  
Forward Link ◽  
User Terminal ◽  
Trade Offs ◽  
Service Areas ◽  
Optimum Solution ◽  
The Cost

The concept of geostationary VHTS (Very High Throughput Satellites) is based on multibeam coverage with intensive frequency and polarization reuse in addition to the use of larger bandwidths in the feeder links, in order to provide high capacity satellite links at a reduced cost per Gbps in orbit. The dimensioning and design of satellite networks based on VHTS imposes the analysis of multiple trade-offs to achieve an optimal solution in terms of cost, capacity and figure of merit of the user terminal. In this paper, we propose a new method for sizing VHTS satellite networks based on an analytical expression of the forward link CINR (Carrier-to-Interference-plus-Noise Ratio) that is used to evaluate the trade-off of different combinations of system parameters. The proposed method considers both technical and commercial requirements as inputs including the constraints to achieve the optimum solution in terms of the user G/T, the number of beams and the system cost. The cost model includes both satellite and ground segments. Exemplary results are presented with feeder links using Q/V bands, DVB-S2X and transmission methods based on CCM and VCM (Constant and Variable Coding and Modulation, respectively) in two scenarios with different service areas.

It's not easy to collaborate, but it's essential!

2017 ◽  
Vol 57 (2) ◽  
pp. 426
Author(s):  
Bernadette Cullinane ◽  
Paul Harrison
Keyword(s):  
Economies Of Scale ◽  
Oil And Gas ◽  
Oil And Gas Industry ◽  
Gas Production ◽  
Structural Factors ◽  
Resource Base ◽  
Gas Industry ◽  
Service Companies ◽  
Trade Offs ◽  
The Cost

While emerging as a world leader in liquefied natural gas production, overall, Australia’s oil and gas industry is disadvantaged by the remoteness and geographical breadth of our operations, our limited infrastructure and insufficient economies of scale. These factors drive up the cost of production and make it difficult for both operators and service companies to balance the trade-offs between building scale and capability. Despite our rich resource base, these structural factors make it challenging for the Australian oil and gas industry to compete globally. Additionally, traditional project development and contracting practices rely on bespoke, bi-lateral agreements between operators and service companies, resulting in inconsistencies and inefficiencies that limit the reuse of solutions and technology, driving costs even higher. This has created an imperative for new collaborative industry platforms in areas of workforce competency management and integrated activity planning, which leverage standardised processes and common infrastructure. This paper will explain how to overcome collaboration obstacles by cultivating a culture of transparency and will discuss the steps undertaken to develop trust within a diverse stakeholder group, enabling the creation of shared solutions. This paper gives concrete recommendations on how to create a new mindset around the appropriate company structure for the development of collaborative and innovative platforms that deliver more competitive outcomes to the Australian oil and gas industry.

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